Question

A brownie recipe requires three and one third cups of sugar to one cup of chocolate chips. If three and three quarters cups of sugar is used, what quantity of chocolate chips will be needed, according to the recipe?

Answer 1

So the range is that combined sugar and chocolate chips you can have [1,10/3] cups.
So far, you have already poured in three and three quarters which in improper fractions is 15/4. Multiply the y-range of the combined with 4, to get this:

12/12 => 40/12. Then multiply 15/4 by three to get 45/12. Clearly you see this that more cups of sugar than the limit is poured. you can only go to 40/12, but 45/12 is just sugar, so no chocolate chips can be added